Were There Any Battles Where Soldiers Saw The Bombing Of Hiroshima and Nagasaki in the Pacific Theatre of World War II? What islands? How close were they to Hiroshima and Nagasaki? Was there a risk of radiation? What are the accounts?
Both Hiroshima and Nagasaki are located on mainland Japan which there were no land battles on, so no chance of them being witnessed by US ground forces.
Hiroshima had roundabout 20.000 POW, mostly from Korea.
Nearly all got killed.
Afaik there was also a few Caucasians:
It is little known that twelve American prisoners of war lost their lives by the Atomic Bomb dropped on Hiroshima. A Japanese victim of the bomb (hibakusha) has recently written a book, which is the result of his years of research and communication with those related to the issue